George Saunders’ sensibility is Pynchon-meets-Wonder Showzen, often taking ideas to illogical extremes: A man objects to ”Samish-Sex Marriage” (”Isn’t it odd that this somewhat effeminate man should be married to this somewhat masculine woman?”). The lead character of a past-its-prime sitcom laments, ”Now it’s basically all mean talk and jokes about poop and butts. He and Doris used to talk about real issues, about them, their relationship…” While Saunders’ send-ups of media-fixated culture tend to blend together, his best tales in In Persuasion Nation — like ”Christmas,” about a 26-year-old back in his hometown with a dead-end roofing job — poignantly capture the struggles of recognizable people.